The present invention relates to a rotary having a pivotable member connected to the rotor so that the pivotable member extends to contact the inner periphery of the casing and is folded according to the position of the rotor in the casing.
A conventional rotary pump is shown in FIGS. 1 and 2 and generally includes a casing 11 with a cylindrical space 12 in which a rotor 13 is rotatably received. The rotor 13 has a shaft 10 connected to a center thereof and the shaft 10 is driven by a proper mechanism so as to let the rotor 13 rotate within the cylindrical space 12. Two passages 14, 140 are respectively defined radially in the rotor 13 and two plates 15, 150 are respectively received in the two passages 14, 140. When the rotor 13 rotates, the two plates 15, 150 are pushed outward to contact the inner periphery defining the cylindrical space 12 by eccentric force. By this way, the liquid in the room between the inner periphery defining the cylindrical space 12 and the rotor 13 can be pushed by the plates 15, 150 from the outlet 122. Liquid enters the room from the inlet 121 because the lower pressure in a partition in the room. However, the plates 15, 150 cannot snugly contact the inner periphery of the cylindrical space 12 as expected so that the efficiency is low.
The present invention intends to provide a rotary pump having a pivotable pushing assembly which can be received in recesses in the rotor or extended to contact the inner periphery of the casing.
In accordance with one aspect of the present invention, there is provided a rotary pump comprising a casing having a rotator rotatably received therein and a shaft fixedly extends through the rotator. The shaft is located eccentrically in the casing. A receiving area is defined longitudinally in an outer periphery of the rotator. An inlet and an outlet are defined through the casing. A pushing assembly has an end pivotally received in the receiving area and the other end of the pushing assembly rotatably contacts an inner periphery of the casing.
The primary object of the present invention is to provide a rotary pump wherein a pushing assembly is pivotally connected to the rotator and an end of the pushing assembly air-tightly contacts the inner periphery of the casing so as to obtain a high efficient pumping feature.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.